Feeding device for cigarette filters and similar rods

ABSTRACT

A device for feeding cigarette filters or similar rod-like articles comprises a fluted drum and a conveyor for feeding a stack-like stream of filters towards the drum and including a conveyor band which is arranged to engage one side of the stack-like stream of filters while moving between two longitudinally spaced guides between which the conveyor is capable of deflecting outwards, in response to the pressure of the filters and against a restraining force, to accommodate a variable quantity of filters in the region of the conveyor band.

This invention is concerned with feeding filters and similar rods of thecigarette industry into flutes of a fluted drum from a mass of rods. Infilter attachment machines, filter rods are commonly fed onto a fluteddrum from a hopper above the drum. An example of such a filterattachment machine is shown in British patent specification No. 1179683.

British Patent Application No. 14940/76 (and corresponding publishedGerman application No. 2716391) describes, amongst other things, anarrangement for feeding rods (double filter cigarette units in thatinstance) onto a fluted drum as a stack-like stream carried towards thedrum by a conveyor with means for controlling the movement of theconveyor to feed the rods in an appropriately controlled manner. Thepresent invention is concerned with improvements over that arrangement,particularly for use in feeding cigarette filter rods onto a fluted drumin a filter attachment machine.

According to the present invention, a device for feeding cigarettefilters or similar rods comprises a fluted drum and a conveyor forfeeding a stack-like stream of filters towards the drum and including aconveyor band which is arranged to engage one side of the stack-likestream of filters while moving between two longitudinally spaced guidesbetween which the conveyor band is capable of deflecting outwards, inresponse to the pressure of the of the filters and against a restrainingforce, to accommodate a variable quantity of filters in the region ofthe conveyor band.

The guides may comprises pulleys around which the conveyor band isarranged to pass. The restraining force is preferably produced by atensioning device for the conveyor band. There are preferably means fordetecting when the conveyor band is deflected outwards to apredetermined extent and for thereupon stopping or slowing down theconveyor; deflection of the conveyor band may be indicated by movementof the tensioning device.

The conveyor may be driven by a constant-torque motor.

Examples of rod-feeding devices according to this invention are shown inthe accompanying drawings.

In these drawings:

FIG. 1 is a diagrammatic elevation of one device.

FIG. 2 is a section on the line II--II in FIG. 1, enlarged to showfurther details;

FIG. 3 is a diagrammatic elevation of a second device; and

FIG. 4 is a diagrammatic elevation of a third device.

In the device shown in FIG. 1, a fluted drum 10 is arranged to receive afilter rod 11 in each of its flutes. The rods are subsequently cut andthen joined to tobacco rods to form filter tipped cigarettes, e.g. inthe manner employed in the Molins PA8 filter attachment machine.

A conveyor comprising two opposed parallel conveyor bands 12 and 13,backed by plates 12A and 13A, conveys a stack-like stream of the filterrods in a generally upward direction towards the drum 10. Each of thebands 12 and 13 is somewhat in the form of a timing belt, i.e. havingdriving teeth (e.g. 13B) whereby it can be positively driven bycorresponding teeth on the pulleys supporting the band; such pulleys forthe band 13 are pulleys 14 and 15, while the band 12 has pulleys 16 and17. In addition each band is formed with rounded ribs 18 extendingacross the band at regular intervals to assist in driving the rodsupwards, each rib having approximately the same diameter as the rods 11.

It should be noted that the stack-like stream of rods is conveyedtowards the drum 10 by the conveyor 12, 13 in approximately a tangentialdirection and is then deflected towards the drum by a pair of bands 19.These bands are shown diagrammatically in FIG. 1 and in fact comprisenarrow timing belts having teeth whereby they are positively driven at aslightly higher speed than the bands 12 and 13. As shown in FIG. 2, thebands 19 pass around end portions 14A, 14B of the pulley 14 and bear onthe rods 11 near their ends. That is to say, the bands 11 are bothlaterally offset from the band 13. In addition, the bands 19 pass aroundpulleys 20 and 21 and are engaged by a gravity-loaded or spring-loadedtensioning pulley 22. This last pulley is carried by a member 23 pivotedat 23A.

In the area adjacent to the drum 10, the ribs 18 on the conveyor 12 areheld out of engagement with the filter rods by fixed plates 10A whichextend respectively across the ends of the pulley 16 and intocircumferential grooves in the drum 10.

When the pressure of the rods on the part of the bands 19 engaging therods is sufficient to deflect the bands outwards into contact with acurved backing plate 24, the roller 22 is lifted to a position in whichthe carrier member 23 engages a microswitch 25 which automaticallyreduces the speed at which the bands 12, 13 and bands 19 are driven. Assoon as the carrier member 23 falls clear of the microswitch 25, thespeed of the drive to the conveyors 12, 13 and bands 19 returns tonormal.

As shown by the arrow in FIG. 1, the drum 10 rotates in acounter-clockwise direction. A refuser roller 26 ensures that no rodsare carried from the stack by the drum 10, apart from those in flutes inthe drum. Between the roller 26 and pulley 20 there is a shortstationary bridge 27.

The stack-like stream of rods is delivered to the conveyor 12, 13 by aconveyor 28 upon which the rods may be delivered from trays and/or froma receiver unit of a pneumatic rod-conveying device such as the MolinsAPHIS. The thickness (height) of the stack-like stream as it approachesthe conveyor 12, 13 is determined by narrow bands 29 passing around apulley 30 and around the ends of the pulley 15 (as in the case of thebands 19 and pulley 14). Further narrow bands 31 lying on opposite sidesof the conveyors 28 and 12 convey the stream of rods around the pulley15. These bands 31 pass around the ends of the pulley 17, around theends of a pulley 32 for the conveyor 28, and around a further pulley 33,and are lightly tensioned by a spring-loaded pulley 34.

The conveyor 28 and bands 31 are formed with driving teeth similar tothose on the bands 12 and 13, while the conveyor 28 also has transverseribs. The drive system may (in a manner known per se) be arranged todrive all the bands and conveyors in unison.

FIG. 3 shows a different form of device according to this invention. Thedevice includes a fluted drum 40 similar to the drum 10 in FIG. 1, andin this example disc knives 41 and 42 are shown for cutting the rodsinto three portions each of which will be secured between two tobaccorods by a uniting band in the course of manufacture of filter-tippedcigarettes in a conventional manner.

A stack-like stream of filter rods 43 is conveyed approximatelytangentially towards the drum by a conveyor comprising bands 44 and 45which are similar to the bands 12 and 13 in FIG. 1. As in the FIG. 1example, a sensor band 46 comprising two narrow portions extending onopposite sides of the conveyor 44 deflect the stack-like stream towardsthe drum 40, this time in a downward direction. A spring-loaded pulley47 carried by a pivoted member 48 performs the same function as theroller 22 in FIG. 1; inward movement of the pulley 47 in response toincreasing pressure of the rods on the operative portion of the bands 46eventually causes the member 48 to operate a switch 49 which reduces thespeed of the conveyors 44 and 45 and bands 46 or possibly brings theirmovement to a temporary stop.

FIG. 3 also shows a tray 50 in position to unload a batch of rods over ahorizontal conveyor band 51 which is driven in unison with the bands 44,45 and bands 46. Between the bands 51 and 45 there is a pair of narrowbands 52 lying on opposite sides of the conveyors 51 and 45 as in theprevious example.

There is also provision for delivery of rods from a receiver of apneumatic rod transport unit such as APHIS 2N. The receiver includesparallel conveyor bands 53 and 54 which deliver a relatively thinstack-like stream of rods into the space above the conveyor 51. For thatpurpose, the receiver may be as described in British Patentspecification No. 1561560.

During normal operation, rods may be delivered from the pneumatic unitvia conveyor 53, 54. However, if the pneumatic delivery unit fails,batches of rods may be delivered manually or automatically from asuccession of trays in any conventional manner.

A refuser roller 55 is included for the reason mentioned in connectionwith FIG. 1.

FIG. 4 shows diagrammatically a different arrangement in which aconveyor comprising a horizontal band 56 and a deflectable band 57 isarranged to convey a stack-like stream 58 of filter rods directlytowards a fluted drum 59. Disc knives 60 and a refuser roller 59A areassociated with the drum 59, as in the previous examples.

A tensioning roller 61 for the band 57 is carried by a lever 62 which ispivoted at 63, and is urged in a counterclockwise direction by a spring64.

Upward pressure of the filters on the band 57 tends to deflect upwardsthe operative lower run of the band 57 passing between the guide pulleys65 and 66. Such movement raises the roller 61; and when a limitingposition is reached, the lever 62 operates a switch 67 which stops orslows down the motor driving the bands 56 and 57. Alternatively, thecontrol arrangement may be such that the motor speed is reducedprogressively as the roller 61 rises.

A pair of bands 68, 69 forming part of the receiver unit of a pneumatictransport system 150 (as mentioned above) delivers a relatively thinstack-like stream of filters to an area 70 above the upstream end of theconveyor band 56. The upper surface 70A of the filters in this area isfree to expand into a space 71 within a cover 72 mounted on supports 73and 74. A beam of light is directed horizontally by a source 75 towardsa photocell 76. When the beam is interrupted by the filters, thepneumatic transport system 150 (including bands 68, 69) is automaticallystopped; and it resumes operation when the beam once again reaches thephotocell 76.

When the pneumatic transport system is out of action, the cover 72 canbe moved off the supports 73, 74 to allow an inverted tray (or asuccession of trays) to be put in its place to continue the supply offilters.

Instead of the conveyor 56, 57 being controlled by the upward deflectionof the band 57, the conveyor may be driven by a constant-torque motor sothat the stack 58 is driven towards the drum 59 with a substantiallyconstant force regardless of the speed of the drum 59 (which wouldnormally run slowly during the machine start-up sequence). A suitablemotor is one which is capable of delivering a constant-torque drive overa speed range extending from zero to the desired maximum speed. Forexample, the motor may be a printed circuit DC motor; one suitablecommercially available example is the ITT Heyneau motor. Alternativelyit is possible to use a shunt-wound motor with a constant field (througha permanent magnet) which is fed with a constant current.

In conjunction with a constant-torque motor, the operative lower run ofthe band 57 may be capable of deflecting upwards (as described above) ormay be constrained to move along a straight path as in the case of theband 56.

Separate constant-torque motors may be provided to drive respectivelythe bands 56 and 57. The torque setting for each motor may beindependently adjustable. For the optimum running condition, forexample, the motor driving the band 57 may be set to produce a lower setor maximum torque than the other motor.

We claim:
 1. In a cigarette filter attachment machine, means for feedingfilter rods comprising a fluted drum for carrying filter rods in theflutes thereof; powdered conveyor means arranged to feed a stack-likemulti-layer stream of filter rods towards the fluted drum wherebymovement of the conveyor means urges the filter rods towards the fluteddrum to ensure that filter rods enter the flutes of the fluted drum, atleast a part of said conveyor means being disposed at a level below thetop of said fluted drum; means defining an expandable area for filterrods above the said part of said conveyor means disposed below the topof the fluted drum and including means upstream of said fluted drum forselectively supporting above the said expandable area a succession offilter-containing trays for feeding filter rods from the trays and ontothe conveyor means; and pneumatic feed means for feedingpneumatically-delivered filter rods into the expandable area above theconveyor means adjacent to the end of the conveyor means remote from thefluted drum, whereby the volume of the filter rods expands in theexpandable area when filter rods enter the expandable area from the feedmeans at a rate greater than that at which filter rods are conveyed fromthe expandable area by the conveyor means.
 2. A filter attachmentmachine according to claim 1, including detecting means for detectingthe height of the filter rods in the expandable area and for controllingthe operation of said feed means in response thereto.
 3. A filterattachment machine according to claim 2, in which the said detectingmeans is mounted at a level above the level of the upper surface of thestack-like stream which is fed from the expandable area by said conveyormeans.
 4. A filter attachment machine according to claim 3, in whichsaid feed means is arranged to feed filter rods into the expandable areaat an entry level below the minimum level of the upper surface of thefilter rods in the expandable area.
 5. A filter attachment machineaccording to claim 1 further including a conveyor band confining theupper surface of the stack-like multi-layer stream of filter rodsadjacent to the fluted drum, said conveyor band being arranged to movebetween two guides between which the conveyor band is capable ofdeflecting outwardly in response to the pressure of the filter rods andagainst a restraining force, and including means for detecting when theconveyor band is deflected outwardly to a predetermined extent and forthereupon reducing the speed of the conveyor means.
 6. A filterattachment machine according to claim 5 in which the restraining forceis produced by a tensioning device for the conveyor band.
 7. A filterattachment machine according to claim 6 in which deflection of theconveyor band is indicated by movement of the tensioning device. .Iadd.8. Apparatus for use in a filter attachment machine for feeding filterrods comprising a fluted drum for conveying filters in the flutesthereof, means defining a filter storage area having an outlet for thepassage of filters towards the drum, filter receiving means forreceiving pneumatically-fed filter rods and for conveying the filterrods into the storage area, means for controlling the delivery of filterrods into the storage area by the filter receiving means to maintain anapproximately-constant quantity of filter rods in the storage area whilethe filter receiving means is in operation, and means for removablymounting a tray at the storage area for delivery of filters from thetray while the filter receiver means is inoperative, characterized inthat the outlet from the storage area is horizontally spaced from thefluted drum and that the apparatus includes conveying means whichextends below the outlet and towards the fluted drum along a lineintersecting the drum for conveying a stack-like stream of filter rodstowards the fluted drum from the storage area..Iaddend. .Iadd.9.Apparatus according to claim 8 in which the filter receiver meansincludes conveying means for conveying the filters substantiallyhorizontally into the storage area..Iaddend. .Iadd.10. Apparatusaccording to claim 9 further comprising means including a refuser rollermounted adjacent to the fluted drum and above the filter rods andarranged to be rotatably driven in the same direction as the drum forpreventing any rods from being carried forward on the surface of thedrum past said refuser roller, any rods tending to be so carried by thedrum being driven by the refuser roller back into the stack-like streamof rods on the conveying means..Iaddend. .Iadd.11. Apparatus accordingto claim 8 in which said conveying means is arranged to convey thefilter rods directly onto one side of the fluted drum..Iaddend..Iadd.12. Apparatus according to claim 11 including confining meansabove the conveying means for confining the rods in the region adjacentto the fluted drum while allowing limited expansion of the stack of rodsin that region..Iaddend. .Iadd.13. Apparatus according to claim 12further comprising means including a refuser roller mounted adjacent tothe fluted drum and above the filter rods and arranged to be rotatablydriven in the same direction as the drum for preventing any rods frombeing carried forward on the surface of the drum past said refuserroller, any rods tending to be so carried by the drum being driven bythe refuser roller back into the stack-like stream of rods on theconveying means..Iaddend. .Iadd.14. Apparatus according to claim 13 inwhich the filter receiver means includes conveying means for conveyingthe filters substantially horizontally into the storage area..Iaddend..Iadd.15. In a cigarette filter attachment machine, means for feedingfilter rods comprising a fluted drum for carrying filter rods in theflutes thereof; powered conveyor means arranged to feed a stack-likemulti-layer stream of filter rods towards the fluted drum wherebymovement of the conveyor means urges the filter rods towards the fluteddrum to ensure that filter rods enter the flutes of the fluted drum, atleast a part of said conveyor means being disposed at a level below thetop of said fluted drum; means defining an expandable area for filterrods above the said part of said conveyor means disposed below the topof the fluted drum and including means upstream of said fluted drum forselectively supporting above the said expandable area a succession offilter-containing trays for feeding filter rods from the trays and ontothe conveyor means; and pneumatic feed means for feedingpneumatically-delivered filter rods into the expandable area above theconveyor means whereby the volume of the filter rods expands in theexpandable area when the filter rods enter the expandable area from thefeed means at a rate greater than that at which filter rods are conveyedfrom the expandable area by the conveyor means..Iaddend.